Fiber optic position and/or shape sensing devices generally comprise a multicore optical fiber (MOF) for determining position and shape of an object. The multicore optical fiber, in turn, typically comprises at least two cores positioned in a relative relationship to one another and spaced apart from each other to reduce mode coupling distortions between the fiber cores. Such devices further comprise an interrogator that transmits light to, and receives reflected light from, the MOF.
However, MOF shape-sensing devices have several shortcomings. First, a MOF can be relatively difficult to couple to an interrogator and require both the MOF and the interrogator to have specialized coupling components. Second, typical MOF exhibits minimal sensitivity to twist. Third, MOFs that feature Fiber Bragg Gratings (FBGs) have the FBGs on each core emplaced in the same relative location and aligned with each other—due to the process by which FBGs are incorporated into the multiple cores of such MOFs during their manufacture—and thus gaps between FBGs are also aligned and thereby define areas for which the MOF cannot monitor. Fourth, compared to single-core optical fibers, MOFs are substantially more expensive to manufacture and very costly to customize from the sole and ubiquitous MOF design universally available today (i.e., where producing any variation would be very expensive if even possible). Finally, most MOF-based sensing solutions utilize Wavelength Division Multiplexing (WDM) which limits the number of FBGs and, in turn, limits sensing precision.